The prior art is replete with computer application programs for generating and editing networks. A network, in this regard, may refer to a manufacturing routing flow diagram, an organization chart, a logic-flow diagram, hierarchical bills of materials, and other similar graphical displays. Such programs generally require the user to input locations of boxes or other nodes that comprise the network and the end points of connecting lines mostly through the use of a graphical pointing device, e.g., a mouse, joystick light pen etc. For instance, in Love et al. U.S. Pat. No. 4,870,561, a mouse is employed to edit a user interface as it is shown on a display. In Barker et al. U.S. Pat. No. 4,703,321 an operator selects one of several editing modes and causes a graphic object (i.e., box, node) to be either redefined in whole or in part. A mouse input is employed by Barker et al. to control the edit action.
Other, more sophisticated network screen editors can be found described in the following articles "On the Design of the Graphical Transition Network Editor" McDaid et al., Lecture Notes In Computer Science, 282 Visualization In Programming, 5th Interdisciplinary Workshop In Informatics and Psychology, May 20-23, 1986, pages 142-150; "Task Master: An Interactive Graphical Environment for Task Specification, Execution and Monitoring" Arthur et al., Behavior and Information Technology, 1989, Vol. 8, No. 3, pages 219-233; "Intelligent Filing System With Knowledge Base" Fujisawa et al., Hitachi Review Vol. 37, 1988, No. 5 pages 323-328 and; "A Network Screen Editor Implementation", Hunter et al., Software-Practice and Experience, Vol. 12, 1982, pages 843-856 (Wiley and Sons). Each of the aforementioned articles describes a sophisticated network editor wherein edit functions are invoked by and through the use of a non-keyboard implement. Furthermore, to the extent that keyboard inputs are employed, editing is accomplished on a keystroke by keystroke basis. For instance, in the Hunter et al. system, a line may be added to the display by pressing a return or tab key, or causing a typing action past a right hand screen margin.
Such inputs are only one aspect of a screen edit function that must be implemented to construct a desired graphical display. In Smith U.S. Pat. No. 4,875,187, a Vector system is used to determine a "pleasing" interconnection matrix for the boxes of a network. However, there is no teaching of how such a matrix can be quickly and easily edited by using simple keyboard inputs.
There is a demand for graphical display functions on relatively unsophisticated personal computers and terminal displays. In providing a network editor for such computers, simplicity of input and commands is desirable. Furthermore, the edit function should provide flexible editing of the display. Moreover, the edit functions should be clearly displayed and understandable so that the user is not intimidated.
Accordingly, it is an object of this invention to provide a network editing system which is operable through a computer keyboard.
It is another object of this invention to provide a user-friendly network editing system, particularly adapted to the generation of hierarchical diagrams.
It is still another object of this invention to provide a network editing system which employs few commands in its edit structure and is easily accommodated by the unsophisticated user.